Differential-speed gearing.



No. 766,438. I PATENTED AUG. 2, 1904.

' H. W. GARDNER.

DIFFERENTIAL SPEED 'GEARING.

APPLICATION FILED SEPT. 21, 1903.

N0 MODEL.

,zfz'inessesx &? a. M

UNITED STATES Patented August 2, 1904.

PATENT OFFICE.

DIFFERENTIAL-SPEED GEARING.

SPECIFICATION forming part of Letters Patent No. 766,438, dated August2, 1904.

Application filed September 21,1903. Serial No. 174,037. No 'model.)

To (all whom it 72m. concern:

Be it known that I, HENRY \VILLLnI GARD- NEE, a citizen of the UnitedStates, residing at Fisher, Louisiana, have invented a certain new anduseful Improvement in Differential- Speed Gearing, of which thefollowing is a full, clear, and exact description, such as will enableothers skilled in the art to which itappertains to make and use thesame, reference being had to the accompanying drawings, forming part ofthis specification, in which Figure 1 is a side elevational view of myimproved differential-speed gearing. Fig. 2 is a top plan view of thesame. Fig. 3 is a vertical cross-sectional view on line 3 3 of Fig. 2,and Fig. 1 is a fragmentary view of the base or casting on which thedifferentialspeed gearing is arranged and illustrates aslightly-modified form of actuating device.

This invention relates to a new and useful improvement indifferential-speed gearing,

the object being to construct a device of the character described whichis portable and which can be applied in any position either verticallyor horizontally without interfering with the operation of the device.This differential-speed gearing is especially designed to drive the feedof other machines to regulate the amount of material fed throughmanufacturing machines. For instance, the gearing is adapted forcontrolling the speed of carriages on turning-lathes, the feed of aspindle of a boring-machine, or the downfeed of a drill-press, givingall graduation required in the feed of any machine.

With these objects in view the invention consists in the construction,arrangement, and combination of the several parts, all as willhereinafter be described, and afterward pointed out in the claims.

In the drawings, 1 indicates the basecasting, and 2 shows journal-boxesin which are mounted shafts 3 and 4, each of said shafts having a pulley5 and 6 on its end, either of which pulleys may be the driving or thedriven pulley, as the case may be. Shafts 3 and *1 have mounted thereondisks 7 and 8, which are tapered from their upper portions toward theirperipheries. Base-casting 1 is formed with guideways,preferably coveredby a removable plate 9, in which guideways are mounted slidingjournal-boxes 10, said boxes carrying a shaft 11. This shaft has ashoulder 12, which may be in the form of a fixed collar, against whichabuts a cone-bearing 13. 1% indicates a companion cone-bearing,preferablyloose on the shaft 11 and facing the cone 13. Thesecone-bearings or take-up collars,

they might be called, carry disks 15, which are so mounted as to have aslight rocking or oscillating movement on their respective cones. 16indicates a spring back of the tapered collar 14, tending to force thesame and its carried disk 15 toward the companion members, the outer endof said spring finding a bearing against a nut 17, threaded on theshaft, by which the tension of the spring may be regulated.

18 indicates a rock-shaft from which extends an operating-lever 19, saidoperatinglever having a 11ranually-operable dog 20, engaging with theteeth of a segment-rack 21, mounted on the base-casting 1. By this meansthe lever and rock-shaft may be adjusted and held in its adjustedposition. I prefer to onlarge the central notch of the segment, as at22, so that when the dog is located therein the operator may know thatthe relation of the pulleysis one to one. \Vhen the dog is located inthe notches to either side of this central notch, the relation of thepulleys is of course changed. I may also arrange two notches 23 at theextreme ends of the segment and isolated from the group of notches, sothat when the dog is in either of these two extreme notches one or theother of the tapered disks is out of engagemement with the companionspring-held disks 15.

The rock-shaft 18 has rock-arms 24 on its ends, to which are connectedlinks 25, said links extending inwardly and being connected to thesliding boxes containing "the shaft 11. Thus when the rock-shaft 18 isoperated the boxes and their carried shaft 11 are moved toward or awayfrom one or the other of shafts 3 and 4, as the case may be.

In operation if we assume that pulley 5 is the driving-pulley when theshaft 11 is adjusted near shaft 3 by moving the hand-lever outwardly tothe last notch of the series it will be obvious that the spring-presseddisks 15 will engage the taper disk on shaft 3 near its axis ofrotation, while said spring-pressed disks 15 will engage the taper diskon shaft 4L farther away from its axis of rotation. Consequently shaft4: will be driven at a lower rate of speed than the driving-shaft 3.According to the proportion of parts shown in the drawings onerevolution of shaft 3 under the conditions just mentioned will driveshaft 4: one-half a revolution. If the hand-lever is now adjustedinwardly, so as to locate the dog in the larger central notch, itfollows as the inner peripheral edges of the springpressed disks l5engage the taper disks on shafts 3 and 4: at equal distances from theiraxis of rotation that one revolution imparted to shaft 3 will drive theshaft 4: the same distance, or one revolution also, By adjusting thehand-lever inwardly to the last notch of the series the peripheralengagement of disks 15 with the taper disk on shaft 3 is farther awayfrom its axis of rotation and nearer to the axis of rotation of thetaper disk on shaft 4:. Consequently under this condition shaft 4 willbe driven at a more rapid rate of speed than shaft 3, the proportion ofthe parts indicated in the drawings being when the handlever is soadjusted two to one. In other Words, shaft I will be rotated twocomplete revolutions while the driving shaft makes one completerevolution.

From the above it will be seen that the ratio of the driving and drivenshafts ranges from two to one to one to two. In the machine shown andwithin this range various intermediate ratios may be obtained byadjusting the dog in the several notches of the segment.

In the event that it is desired to throw out the differential gearing ofany kind it is only necessary to move the hand-lever to the extremenotch in either direction to disengage either one'of the taper disksfrom the companion disks 15.

Instead of using the hand-lever to make the adjustments of the companiondisks a rock-arm 30, depending from shaft 18, may be employed, saidrock-arm being connected to a link or lever, so that thedifferential-speed gearing may be adjusted from a distance, asillustrated in Fig. 4.

By adjusting the tension of spring 16 on shaft 11 it will be evidentthat the friction of the disks 15 on the taper disks may be increased ordiminished. It will alsobe noted with respect to my differential-speedgearing that the same acts like a friction-clutch with respect to asuddenly-applied load on the machine to which power is being imparted.Any resistance on the part of the driving-shaft and speed-gearing devicewhich is too great to be overcome by the friction contact of disks 15will permit either the driving taper disk or the disks 15 to rotateindependently Without danger of forcing the machine to which power isbeing transmitted, and thus accidents and breakage are avoided.

The taper or cone collars 13 and 14 permit companion 'disks 15 toaccommodate themselves to various adjustments and impose but littlefrictional resistance to the operation of the device. Of course there isalso friction between the inner peripheral edges of the disks 15 and thetaper disks on the shafts 3 and a; but this is not a serious objection,as it is a rolling friction and does not impede or retard the freemovement of the parts to any appreciable extent. In fact, there is nolateral or transverse thrusts on any of the shafts due to frictionalresistance, the device running free at all times.

I am aware that minor changes in the construction, arrangement, andcombination of the several parts of my device can, be made andsubstituted for those herein shown and described without in the leastdeparting from the nature and principle of my invention.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In a differential-speed gearing, a supporting-base having parallelguideways, journal-bearings slidable in said guideways, removablelocking-plates extending over the guideways to secure the bearingstherein, a shaft carried by the bearings, clutch means carried by theshaft, and rotatable disks mounted in fixed bearings on the base and forengagement by the clutch means.

2. In a differential-speed gearing, a supporting-base having parallelguideways, journal-bearings slidable in said guideways, arched lockingmeans secured to the base and bridging the guideways to slidably securethe journal-bearings therein, a shaft carried by the bearings, clutchmeans carried by the shaft, and rotatable disks mounted in fixedbearings on the base and for engagement with the clutch means.

3.'In a differential-speed gearing, a supporting-base having parallelguideways, journal-bearings slidable in said guideways, removablelocking-plates extending over the guideways to secure the bearingstherein, a shaft carried by the bearings, clutch means carried by theshaft, rotatable disks mounted in fixed bearings on the base and forengagement by the clutch means, a rock-shaft carried by the base,link-connected to the bearings and the rock-shaft, and means foractuating the rock-shaft.

4. In a differential gearing, a base having a pair of rotatable disks infixed bearings, a clutch means for variable engagement with therespective disks, sliding bearings carrying said clutch means, means formoving the bearings to a predetermined position with relation to thefirst-named disks, said bearingmoving means comprising a pivoted levercon- IIO nected to the bearings, a dog carried by the lever, a rack-barfor engagement by the dog, the teeth of the rack being spaced apart atintervals to a greater degree than spaces of the teeth adjacent thereto,to indicate the degree of engagement of the clutch means with the disk.

In testimony whereof I hereunto afiix my signature, in the presence oftwo witnesses, this 16th day of September, 1903.

HENRY XVILLIAM GARDNER.

Witnesses:

(J. P. DUNCAN, T. R. MALIN.

